Different networks have different features and consequences of use. For example, a prevalent cost which is incurred in connection with using a cellular based radio telephone systems are connection charges, which typically accumulate in proportion to the amount of cellular resources used in making a call, which is often measured in terms of the duration of a call. This is due at least in part to the ongoing costs of operating and maintaining the cellular based infrastructure, including costs of the equipment, the power necessary for operating the equipment, and the airwave resources in the form of the licensed frequency spectrum.
However the cellular networks typically benefit from a relatively large coverage area, which enables a communication connection to be established and maintained over the same. Nevertheless, there are environments within the coverage area of a network in which cellular connections have historically experienced some degree of degradation, such as inside a building, where the walls and the roof of the building can reflect and/or absorb the cellular signals.
Alternatively, wireless local area networks have been developed for providing localized wireless connectivity between various devices and a packet data network, such as the Internet. While a cellular signal may have difficulty penetrating some buildings, wireless networks are often deployed in such a manner so as to specifically provide communication coverage within a building. Furthermore, the cost of deploying and maintaining a wireless local area network, is traditionally much less, due at least in part to the shorter transmission ranges, which results in the ability of the network to use less expensive equipment, which correspondingly uses less operational power. Still further because the transmission ranges are shorter, there is less possibility of interference between networks, and so the same shared frequencies can generally be re-used, which enables the network to be deployed without needing to obtain a license for dedicated frequencies, and in fact generally make use of a common set of shared frequencies which have been specifically set aside for such an application.
Still further, the evolution of the various networks including for example the expansion of the cellular networks to support packet data services and enable connectivity to the Internet, has generally resulted in many of the wireless local area networks and the cellular networks having common points of connection through which information can be conveyed between the networks. The common points of connection, in turn, can be used to create alternative communication paths between the mobile stations and the one or more networks, thereby potentially enabling the mobile subscriber to selectively make use of each of the networks in establishing a communication connection, which allows one greater control in attempting to make more optimal use of the available network resources. Still further, the mobile station will have greater flexibility if the mobile station could facilitate the transition between the various alternative communication paths at any time including when a current communication connection already exists, in addition to when a mobile station may be idle.
Consequently, a wireless communication device and method, which is capable of making a secure transfer of a mobile station communication connection from a direct connection with a cellular network to a connection via a wireless local area network, would be beneficial.